Uber interview question
The challenge had 3 parts: SQL, Experiment Design, and Machine Learning. In the SQL portion you had to write some queries to answer complicated real world questions (without any data given, just a schema). In the experiment design portion you are asked to create a hypothetical plan to answer testing a new app. In the Data Science portion, you are asked to perform binary classification on a given data set, and return insights from the classification.
Interview Answer
Anonymous
The SQL questions were to write executable code with quite complex problems, that took me about 70 lines of SQL each. I wrote about a page outlining a randomized experiment to test the efficacy of a new app. In the classification problem, I used random forest as a classifier and reported on the feature importances.